光合成はピコ秒のスケールで再接続される
Tomi K Baikie1, Laura T Wey2,3, Joshua M Lawrence2,4
1Cavendish Laboratory, University of Cambridge, Cambridge, UK.
Nature
|March 23, 2023
まとめ
科学者たちは 細胞の光システムIと光システムII (PSIとPSII) から 電子を 直接 抽出することに成功しました この光合成の研究の突破は,バイオハイブリッドエネルギー技術の新たな可能性を開きます.
科学分野:
- 光合成の研究
- バイオエネルギー
- バイオテクノロジー
背景:
- 光学系IIとI (PSII,PSI) は光合成に不可欠であり,水の酸化と電子の活性化を促進します.
- 現在の研究は,効率の向上とH2進化のような新しいアプリケーションのために光合成を"再接続"することを目指しています.
- 以前の方法は,端末受容器での電荷抽出に焦点を当てて,熱力学的増益を制限していました.
研究 の 目的:
- PSIとPSIIの光刺激反応センターから直接早期の電子抽出の可能性を調査する.
- 光学系の構造の中で 反応の中心はアクセスできないという 長い間信じられてきた信念に 異議を唱えるためです
- 生物技術の応用のために光合成プロセスを操作するための新しい道を探求する.
主な方法:
- 超高速吸収 (TA) スペクトロスコーピーを in vivoで利用した.
- 生きたシアノバクテリア細胞と 孤立した光システムを使用した.
- 2,6-ジクロル-1,4-ベンゾキノン (DCBQ) とメチルビオロゲンなどの外来電子媒介剤を使用した.
主要な成果:
- 光刺激されたPSIとPSIIから電子の抽出が成功していることが実証された.
- 初期段階での電子抽出を 撮影後数ピコ秒で達成した
- 媒介体が外部のクロロフィルの色素を局所外的な電荷移転状態で酸化すると仮定した.
結論:
- この研究は,現存する光学系隔離モデルに挑戦しています.
- 光学系から早期の電子抽出は可能である.
- 生物技術と半人工合成のための光合成の研究と再配線のための新しい道を開きます.
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